If they win the match, their next game could be at the 82,300-capacity Croke Park in Dublin in the All-Ireland quarter-finals.

"It's hard to explain and put into perspective. It's a dream," Noel O'Sullivan, the chairman of the London County Board, told BBC London 94.9.

"I've been involved for over 40 years and we always aspired to win one game in Connacht.

London Gaelic Athletic Association

Formed in 1896

Based in Ruislip, west London

Won the All-Ireland Senior Hurling Championship in 1901

Have competed in the Connacht Senior Football Championship since the 1970s

Before this year their only senior victory had come in 1977

Reached the Connacht SFC Final for the first time in 2013

"To reach the final has been unbelievable."

The London GAA (Gaelic Athletic Association) was formed in 1896 to give the Irish community in England's capital an opportunity to play Gaelic football and hurling and has formed the focal point for what is now a thriving youth and club system.

Their formative years were successful, with the side winning the All-Ireland Senior Hurling Championship in 1901, but prior to this year they had only won one senior game of Gaelic football.

Since the 1970s the club have competed in the Connacht Senior Football Championship, one of four similar competitions in the provinces of Leinster, Ulster and Munster, which culminate in the All-Ireland Championship.

Such is the size and spread of the Irish diaspora that a team from New York in the United States also compete in the Connacht SFC.

"We've had three hard games and they are hot favourites," London manager Paul Coggins said.

"The lads are all willing to be the best they can be.

"It's down to the last 12 and it's knockout football. We're hoping for a huge performance."

Gaelic Football basics

Gaelic football is one of the biggest sports in Ireland: a 15-a-aside field game which is played on a pitch up to 145m long and 90m wide.

The goalposts are the same shape as on a rugby pitch, with a lower crossbar, and a goal tended by a keeper.

The ball can be carried in the hand for a distance of four steps and can be kicked or "hand-passed". After every four steps the ball must be either bounced or "solo-ed" (an action of dropping the ball onto the foot and kicking it back into the hand). Players may not bounce the ball twice in a row.

To score, you put the ball over the crossbar by foot or hand / fist for one point or under the crossbar and into the net by foot or the hand / fist (in certain circumstances) for a goal, the latter being the equivalent of three points.

London beat Leitrim by a one point margin last month - an experience Coggins believes will prove useful in the Connacht final.

"We are well up for it," he said.

"Belief is a powerful ally. We had two games against Leitrim which were fierce and competitive.

"Playing close games and getting over the line against good, competitive teams who have a great tradition in Connacht gives belief and determination."